Ventura Water (Calif.) is aiming to curb water waste with the use of the city’s first Neutral Output Discharge Elimination System Unit (NO-DES).
The unit, essentially a water filtration system on wheels, replaces the conventional method of flushing the city’s fire hydrants to remove harmful particles from the water distribution lines.
Rather than flushing water out of the lines and into the streets and storm drains, the NO-DES truck uses a trailer-mounted pumping, filtration, and re-chlorinating system that circulates water through the distribution unit, according to Ventura Water spokesperson Craig Jones.
A pump on the truck circulates the water as it passes through a series of filters. From there, the filters remove sediment and particles, even adding disinfectant if needed, before the water is pumped back into the city’s pipelines.
While periodically flushing the pipelines is necessary to maintain the quality of drinking water, the conventional method of pumping it into the street isn't well received by residents who are asked to conserve water during a drought, Jones said.
Ventura Water’s truck, which was paid for through the city’s accumulated fleet replacement funds, cost $450,000. The annual cost of maintenance, fuel, and future replacement accruals is likely $48,000, said Mary Joyce Ivers, CPFP, fleet and facilities manager for Ventura Public Works.
The NO-DES unit is expected to save 10 million gallons of water annually, Jones said. Within the first week of operation alone, it saved an estimated 650,000 gallons.
While the NO-DES unit is expected to take longer than conventional methods and require more staff, it will also provide diagnostics on the water system. For example, areas that have higher particles will be evident by how quickly the filter in the system needs to be changed. This will help the water department prioritize which areas need to be filtered at higher frequencies and which ones don’t.
Aside from the scheduled flushing of the lines, Jones said the city plans to use the unit to clean reservoirs, lines after emergency repairs, new construction tie ins, backwash granular activated carbon (GAC) filters, and after natural disasters.
The City of Ventura is not the first municipality to employ a water filtration truck. According to the manufacturer's website, NO-DES units have been previously purchased by the California cities of Pasadena, San Jose, and Fresno, and the Detection Services of Australia.